Method of forming composite packaging material



Jam. 4,, 1966 J. F. HELM s ETAL 3,227,054

METHOD OF FORMING COMPOSITE PACKAGING MATERIAL Original Filed July 26, 1963 6 Sheets-Sheet 1 INVENTORS J'GHIV F. HEZ M6 Jan. 4, 1966 J. F. HELMS ETAL 3,227,054

METHOD OF FORMING COMPOSITE PACKAGING MATERIAL Original Filed July 26, 1963 6 Sheets-Sheet 2 Jan. 4, 1966 J. F. HELMS ETAL 3,227,054

METHOD OF FORMING COMPOSITE PACKAGING MATERIAL Original Filed July 26, 1963 6 Sheets-Sheet 5 Jan. 4, 1966 J. F. HELMS ETAL 3,227,054

METHOD OF FORMING COMPOSITE PACKAGING MATERIAL Original Filed July 26, 1963 6 Sheets-Sheet 4 Jan. 4, 1966 J. F. HELMS ETAL 3,227,054

METHOD OF FORMING COMPOSITE PACKAGING MATERIAL Griginal Filed July 26, 1963 6 Sheets-Sheet 5 Jan. 4, 1966 J. F. HELMS ETAL 3,

METHOD OF FORMING COMPOSITE PACKAGING MATERIAL Original Filed July 26, 1963 6 Sheets-Sheet 6 M/z zt United States Patent Ofifice 3,227,054 METHOD OF FORMING COMPOSITE PACKAGING MATERIAL John F. Helms and Morris W. Kuchcnbecker, Neenah, Wis., 'assignors to American Can Company, New York, N.Y., a corporation of New Jersey Continuation of application Ser. No. 297,861, July 26, 1963. This application June 14, 1965, Ser. No. 463,758 9 Claims. (Cl. 93-1) This application is a continuation of application SN. 297,861, filed July 26, 1963, by Morris A. Kuchenbecker et al. for Method of Forming Composite Packaging Material.

This invention relates generally to improved lined cartons for the packaging of liquids. More specifically, the invention relates to a method of making composite carton blanks, the blanks resulting therefrom and the cartons formed from the blanks to be used for the packaging of fruit juice concentrates.

Various containers for the packaging of liquids have been proposed before, but such containers have possessed one or more of the following undesirable properties: wicking of the edges of the packaging materials in contact with the liquid; leakage at the corners due to im proper sealing of the ends of the package; insufficient strength in the packaging materials to prevent distortion and rupture of the seals; inability to be formed, filled and sealed on high speed automatic equipment; and difficulty in ganing access to the contents.

It is therefore an object of the present invention to provide producing composite carton blanks which can be readily set up, filled and sealed on automatic machinery to form improved, liquid-tight packages.

According to the present invention a composite packaging material is formed by laminating together die-cut paperboard, foil, and tissue employing adhesives and heat scalable coatings, such as polyethylene, to produce a composite web. The web is then passed through a cutting means and separated into individual blanks, which can be readily set up, filled and sealed to form a liquid-tight sealed package.- Access to the contents of the package is easily gained by a tear strip opening means. Furthermore, coupled with the stated object are the ancillary objects of a construction which provides adequate protection t the contents of the container, prevents wicking of the packaging materials and permits ready opening of the closed container for access to the contents.

Further details, advantages and objects will be apparent from the following specification and appended drawings wherein:

FIGURE 1 is a diagrammatic representation of a method of continuously converting suitable materials into a composite web for use as container linings.

FIGURE 2 is a diagrammatic representation of a method for forming a composite web to be cut into container blanks.

, FIGURE 3 is a plan view of a portion of a paperboard web after passing through a first cutting station prior to lamination to the composite web made as shown in FIG- URE 2.

FIGURE 4 is a plan view of a portion of the composite web of FIGURE 2 after passing through a second cutting station.

FIGURE 5 is a plan view of an integral carton blank resulting from separation of the composite web of FIG- URE 2 after passing through the second cutting station.

FIGURE 5A is an enlarged fragmental sectional view of the carton blank taken along line 5A-5A of FIGURE 5 showing the composite layers of the blank.

FIGURE 6 is a partial perspective View of the blank of 3,227,054 Patented Jan. 4, 1966 FIGURE 5 partially set up and glued to form a carton shell.

FIGURE 6A is an enlarged fragmental sectional view of the carton shell taken along line 6A-6A of FIG- URE 6.

FIGURE 7 is a partial perspective view similar to FIG- URE 6, showing the folding and sealing of the lining material.

FIGURE 8 is a partial perspective view showing a further state in forming the completed carton.

FIGURE 9 is a partial perspective view showing yet a further state in forming the completed carton.

FIGURE 10 is a partial perspective view of the completed carton, and

FIGURE 11 is a partially perspective view of the complet d carton having the tear strip opening means partially removed.

Referring first to FIGURE 1, there is shown a continuous method for converting frangible materials into a web of liner material having a tear tape attached thereto. Initially, a roll 1 of paper tissue is unwound from an unwind stand and the leading edge threaded through the various rolls in the manner shown in FIGURE 1. The tissue passes over pressure roll 2 into a nip formed by a pressure roll 2 and a colling drum 4. A second roll 5 of metal foil is unwound, passes over the colling drum 4 and into the nip. The two webs are laminated together by polyethylene from an extruder 3 positioned directly above and immediately adjacent the nip. After passing through the nip, the liner web is cooled by the drum 4 to reduce the temperature to about 70 F. Next, the liner web passes over idler rolls 6 and 7 and between back-up roll 9 and gravure roll 10. An anchor coating solution 8 is transferred by gravure roll 10 onto the paper side of the liner web. The web then passes over idler roll 11 and into a drying chamber 12 where it is supported by a series of rollers 13. The length of the chamber 12 is determined by the rate of travel of the web, the drying time of the anchoring solution and the temperature in the chamber.

After completion of the drying, the web travels under idler roll 14 and over a second pressure roll 15, which together with a second colling drum 21 forms a second nip. A plurality of tape-unwinds or dispensers 17 are mounted in side by side relationship to unwind rollsof tape 16 and 18, which are fed between guide rolls 19 into the nip. The tapes are spaced transversely across the web and ensure even winding of the liner web. A second extruder 20 is positioned over the nip formed by pressure roll 15 and colling drum 21 and extrudes poly ethylene onto the tear tape 111 and liner web. The polyethylene firmly positions the tear tape on the composite web as well as providing a protective coating for the foil surface. After leaving the cooling drum 21, the web travels over idler roll 22. A roll of interleaving material such as paperboard, 23a is unwound and rewound with the liner web to form roll 23. The interleaving material is approximately equal in thickness to the tear tapes and spaced between them to insure proper rolling of the web. The roll 23 is then transferred to a second line shown in FIGURE 2 where it is laminated to a web of frangible material, such as paperboard, to form a composite web which is cut into carton blanks.

The second line includes laminating, cutting and separating means. A roll of paperboard 24 is unwoundand fed under idler roll 25 and over back-up roll 27. Tension control rolls 26 maintain the paperboard web in tight frictional contact with the back-up roll 27. The paperboard web then travels around eccentric feed-up roll 28, over idler roll 29 into a first cutting section 30, over idler roller 31, around eccentric take-off roll 32 and between tension control rolls 33 and back-up roll 34.

Eccentric feed-up and take-off rolls 28 and 32, respectively, provide alternating periods of slack and tension in the web permitting use of a reciprocating cutting means 30.

A comparison of the portion of the paperboard web of FIGURE 3 and a separated blank of FIGURE shows the relationship between the initial cuts in the web and the completed blank. The cuts shown in FIGURE 3 are impressed on what is ultimately the interior side of the blank. Cuts 76 and 77 extend only partially through the board while the remainder of the cuts are through the entire thickness of the web. In addition to defining cut out portion 89a (see FIGURE 5) the cut lines define the side edges of flaps 86-88 and 91-93.

After passing through cutting means 3t and the rolls associated therewith, the web travels over idler rolls 35-37 and between gravure roll 38 and back-up roll 45. An adhesive 39 is applied to what is ultimately the inner side of the carton blank by gravure roll 38. The adhesive coated web next travels around idler rolls 41 and into a nip formed by a pair of pressure rolls 42. Roll 23, which is adjacent pressure rolls 42, is unwound and fed into the same nip and laminated to the paperboard web with the tear tape and foil on the outside. As the roll 23 is unwound the interleaving material is transferred to a winding roll 23a.

The laminated web then travels over a series of idler rolls 43-45 and between back-up roll 46 and tension control rolls 46a where it is maintained in tight frictional contact with the rolls. The composite web then travels over eccentric feed-up roll 47 to provide alternating periods of slack and tension for reciprocating cutting means 50. Idler rolls 47a, 48 and guide rolls 49 feed the web into the cutting means 50 where a cutting and creasing operation is performed on the web prior to separation of the blanks in the separating unit 51 and transfer to the stacking table 52.

Referring to FIGURES 4 and 5, the relationship between the second web cutting operation and the finished blank is shown. Cut lines 74 and 75 extend only partially through the thickness of the paperboard from the outside surface. Other cut lines 53-58 extend entirely through the composite web and define the individual blank. Score lines 60-73 are impressed on the web to provide fold lines for the various panels and flaps.

FIGURE 5 shows the outside of a completed composite blank. The blank is divided by score lines 60-73 into panels and flaps including main panels 80-54 and end flaps 85-94. A tear strip having a pull tab 95 is defined on the inside of the paperboard layer by partial cut lines 76-77 and on the outside by partial cut lines 74-75. The liner composed of tissue, foil and polyethylene and having the tear tape (see broken lines 111) thereon is coextensive with the outer generally rectangular configuration of the paperboard layer. Portions 97-102 of the lines are visible in FIGURE 5. FIGURE 5A is a fragmental sectional view of the composite blank taken through the area of the tear tape. The various layers and typical material used in the carton blank shown in cross-section in FIGURE 5A are as follows:

layer Mil-Polyethylene, ten pounds per ream layer 111cotton or rayon tear tape coated with a heatsealable material and about .007 inch thick layer 112polyethylenimine anchor coating layer 113-alurninum foil, .00035 inch thick layer 114-polyethylene, ten pounds per ream layer 115-paper tissue, sixteen pounds per ream layer 116vinyl acetate adhesive, five pounds per ream layer 117paperboard, .0012 inch thick layer 118polyethylene, ten pounds per ream The blank is formed into a shell about a rectangular mandrel with the foil on the inside. Main panels 81, 82 and 83 are folded about their connecting score lines to positions of contact with three sides of the mandrel. Next,

main panel is folded about score line 61 to lie inclined at an angle of about thirty degrees to the remaining mandrel wall. The liner, which is not adhered along the longitudinal free edge of main panel 80, is separated from the main panel 80 folded against the remaining wall of the mandrel. The main panel 84 is folded inwardly about score line 62 and the edge thereof inserted between the unadhered portion of the liner and the edge of main panel 80. The pull tab 5'5 is kept on the outside surface of main panel 80 to facilitate opening of the completed carton. The cut out 8% is necessary to obtain both the split seam and the cross over of the pull tab on the outside of the carton. Sealing heat and pressure are then applied to all of the overlapped areas, except the tear tab 95 to produce the squared shell shown in FIGURE 6. FIG- URE 6A shows the split seam with main panel 84 between the liner and main panels 80.

After forming the squared carton shell, usually one end is closed and sealed, the carton filled, and the other end closed and sealed. Since the closing and sealing steps for both ends of the carton are the same, reference is had to closing and sealing just one end of the carton.

The carton is closed and sealed by first forming a fin seal, as shown in FIGURE 7, with the projecting liner which is not adhered to the end flaps. The liner after folding is sealed by the application of heat and pressure to obtain adhesion between the polyethylene bearing surfaces. Next end flap $7 is folded inwardly about its connecting score line 66 to lie superposed on the carton liner. The sealed portion of the liner is then folded down to overlie end flap 87 as shown in FIGURE 8. End flaps 85, 89 are folded down on the liner and then end flap 88 is folded inwardly to overlie overlapped end flaps 87, and $5, 89, ass hown in FIGURE 9. The closure is completed by infolding end fiap 86 into overlapping relationship with end flap 88 and applying sealing heat and pressure to adhere the two flaps in the overlapped area. The completed sealed carton is shown in FIGURE 10.

The carton is opened by grasping pull tab 95 and pulling outwardly away from main panel 81 towards main panel 83. Exposure of the contents is obtained by consecutively pulling the tear strip through main panels 84, 83, 82, 81 and 85 thus freeing the portion of the carton above the tear strip. The contents can then be readily dispensed from the remaining receptacle portion of the carton.

The particular opening action of the tear strip is illustrated in FIGURE 11. The inner layer of polyethylene (shown in FIGURE 5A) overlying the tear tape 111, due to its adhesion to the tear strip, is removed with the tear tape. Tear tape 111, being of greater strength than the foil-tissue combination, causes rupture of the combination along the edges of the tape. Cut lines 76 and 77 in the inner surface and 74 and 75 in the outer surface of the paperboard facilitates removal of the tear strip. The paperboard peels from the inner end of cut lines 76 and 77 in the interior of the paperboard, to the interior ends of cut lines '74 and 7 5. Therefore in the area between the cut lines in the removed tear strip the thickness of the paperboard is substantially one-half of the original thickness. The relationship between the thickness of the layers shown in FIGURE 5A is varied with regard to the protection desired and the ease of removal of the tear strip.

The present invention provides a liquid-tight container, which has a tear strip opening means giving easy access to the contents of the container. Since the liner completely encloses the product and prevents exposure of the paperboard to the product, wicking of the exterior of the carton is prevented. Extruding polyethylene over the tear tape firmly adheres it in place as well as protecting it from deterioration due to product contact. Although exemplified with polyethylene, it is obvious that other extrudable film materials could be employed. The overlapping of the pull tab on the outside of the carton provides easy access to it for opening purposes.

It is understood that the size and shape of the blank and hence the carton, and that the specific materials from which they are formed can be varied in numerous ways by those skilled in the art without departing from the spirit of the invention.

We claim:

1. A method of forming a composite packaging material which comprises passing a flexible material into a nip formed by two rolls, aligning a tear tape on said material immediately before the entry of said material into the nip, extruding a layer of film material which adheres to said flexible material over said tear tape and an adjacent portion of said flexible material to position said tear tape on said flexible material, cooling said film material during its passage between said rolls, laminating said flexible material to paperboard material, and providing a line of weakness in the composite laminated material positioned adjacent and parallel to said tear tape, said line of weakness not extending through said flexible material.

2. The method of claim 1 wherein the film material is polyethylene.

3. A method of forming a composite packaging material which comprises passing a continuous web of liquid impervious sheet material into a nip formed by a cooling drum and a back-up roll; aligning a tear tape on a surface of said web immediately before the entry of said web into the nip, extruding a layer of molten film material, which adheres to said web, over said tear tape and a portion of said web surface position said tear tape on said web, passing the web over the cooling drum to set the film material, and laminating the other surface of said web to paperboard material with said tear tape in alignment with a line of weakness in said paperboard material.

4. The method of claim 3 wherein the film material is polyethylene.

5. A method of making a composite carton blank which comprises laminating together a layer of metal foil and paper tissue to form a first web, positioning a tear tape on the foil side of said first web, extruding a layer of polyethylene over said foil and tear tape thereon to secure said tear tape as positioned, passing a second web of paperboard through a first cutting means to make flap defining cuts and lines of weakness defining a tear strip therein, laminating said first and second webs together with the tissue side of said first web adjacent said second web and the tear tape between said lines of weakness,

and passing a composite web formed by said first and second webs through a second cutting means which cuts said composite Web into individual composite carton blanks.

6. A method of making a composite carton blank which comprises laminating together a layer of metal foil and paper tissue to form a first web, positioning and affixing a tear tape on the foil side of said first web, passing a second web of paperboard through a first cutting means to make flap defining cuts and lines of weakness defining a tear strip therein, laminating said first and second webs together with the tissue side of said first web adjacent said second web and the tear tape between said lines of weakness, and passing a composite web formed by said first and second webs through a second cutting means which cuts said composite web into individual composite carton blanks.

7. A method of making a composite carton blank which comprises laminating together a layer of a liquid impervious material and a layer of paperboard to form a composite web, applying a tear tape to the exposed surface of said liquid impervious layer, extruding a layer of thermosplastic material over a portion of said liquid impervious layer and said tear tape thereon, and passing said web through a cutting and scoring means to form individual cut and scored carton blanks including at least one line of weakness in said paperboard adjacent and parallel to said tear tape, said line of weakness being of predetermined depth so as not to extend through said liquid impervious layer.

8. The method of claim 7 wherein said liquid impervious layer comprises metallic foil.

9. A method of making a composite carton blank which comprises laminating together a layer of a liquid impervious material and a layer of paperboard to form a composite web, adhesively applying a tear tape to the exposed surface of said liquid impervious layer, and passing said web through a cutting and scoring means to form individual cut and scored carton blanks including at least one line of weakness in said paperboard adjacent and substantially parallel. to said tear tape, said line of weakness being of predetermined depth so as not to extend through said liquid impervious layer.

References Qited by the Examiner UNITED STATES PATENTS 3,057,539 10/1962 Leary 156-244 FRANK E. BAILEY, Primary Examiner. 

1. A METHOD OF FORMING A COMPOSITE PACKAGING MATERIAL WHICH COMPRISES PASSING A FLEXIBLE MATERIAL INTO A NIP FORMED BY TWO ROLLS, ALIGNING A TEAR TAPE ON SAID MATERIAL IMMEDIATELY BEFORE THE ENTRY OF SAID MATERIAL INTO THE NIP, EXTRUDING A LAYER OF FILM MATERIAL WHICH ADHERE TO SAID FLEXIBLE MATERIAL OVER SAID TEAR TAPE AND AN ADJACENT PORTION OF THE FLEXIBLE MATERIAL TO POSITION SAID TEAR TAPE ON SAID FLEXIBLE MATERIAL, COOLING SAID FILM MATERIAL DURING ITS PASSAGE BETWEEN SAID ROLLS, LAMINATING SAID FLEXIBLE MATERIAL TO PAPERBOARD MATERIAL, AND PROVIDING A LINE OF WEAKNESS IN THE COMPOSITE LAMINATED MATERIAL POSITIONED ADJACENT AND PARALLEL TO SAID TEAR TAPE, SAID LINE OF WEAKNESS NOT EXTENDING THROUGH SAID FLEXIBLE MATERIAL. 